Question

A hydrogen balloon at the Earth's surface has a volume of 6.0 m3 on
a day when the temperature is 27° C and the pressure is 1.00 105
N/m2. The balloon rises and expands as the pressure drops. What
would the volume of the same number of moles of hydrogen be at an
altitude of 40 km where the pressure is 3.70 102 N/m2 and the
temperature is -18° C?
m3